1. Field of the Invention
The present invention relates to an electric vehicle which has a battery carrier for containing a battery disposed on a vehicle body thereof. More particularly, it relates a body structure and a battery-supporting structure for the electric vehicle.
2. Description of the Related Art
Research and development has been carried out on electric cars as a way of providing a pollutant emission-free vehicle. Most of such electric cars use a battery in combination with either an alternating-current motor or a direct-current motor as a power source. The battery is usually accommodated in a battery carrier which is anchored to the underside of a vehicle body by means of bolts and the like. (Refer to Japanese Patent Application Laid-Open No. 60-146724.)
In order to reduce impact force due to a collision, a conventional automobile is designed to permit front-side members and the like to be deformed, thereby absorbing kinetic energy which would otherwise be transferred to the vehicle body thereof.
However, an electric vehicle having a battery has greater body weight than ordinary vehicles. Thus, absorption of kinetic energy requires a corresponding increase in the strength of the front-side members and the like, which further increases body weight.
To solve this problem, an electric vehicle which allows a battery carrier housing a battery to be separated from a vehicle body has been proposed for a vehicle in a collision. (Refer to DT2522844A1). However, this type of electric vehicle only drops the battery carrier to a road surface. It is not disclosed in DT2522844A1 how to manage finally the kinetic energy of the battery carrier.
Another type of electric vehicle has been proposed in which a battery, movably disposed on a crushable rear body of the vehicle, is connected thereto by means of a plurality of connecting means. The kinetic energy of the battery, which is caused by a collision of the vehicle, is thereby absorbed through crush of the rear body. (Refer to DE3141164A1.)
The rear body of this electric car, however, is fabricated to acquire relatively low strength because it is used as a means for absorbing the kinetic energy of the battery. Accordingly, the above strength of the rear body greatly differs from the strength of the rear body, which is required for absorbing impact loading due to a collision at the rear body. This means that this type of car may be an electric vehicle having a very particular rear body structure, which is designed to accommodate only an impact of a front body thereof, because it is very difficult to make the absorption of the kinetic energy of the battery compatible with the absorption of such impact loading. Accordingly, a rear body structure for coping with a bump of the rear body provides no control over the kinetic energy of the battery.